Very impressed with De Los Santos and Medina.
De Los Santos was throwing 94-96, has a plus changeup and his breaking ball showed promise, though still a work in progress, If he can improve his command and that breaking ball in LHV this summer, he's a great insurance policy, with a third pitch he's mid-rotation starter material.
Medina throws as hard, and showed a plus breaking ball, struggles a little to locate and overthrew a few, but it has a strong break. Needs to add a changeup, but he's going to be in Reading has plenty of time.
Alvarez has LOOGY stuff, 91 FB, breaking ball, change.
Morgan was throwing 93 with a nice breaking ball, I think he'll beat out Alvarez if he can show consistency.
Rios throws hard, but lack of command will probably keep him in AAA the rest of his career.